1. Field of the Invention
This invention relates to overhead garage doors and, more particularly, to a tension strut apparatus and method for stiffening or otherwise supporting and also selectively applying tension to the sections of an overhead garage door thereby correcting or creating a predetermined degree of curvature in the section.
2. The Prior Art
Overhead garage doors are well-known and are used as closures for large openings such as garage and warehouse entrances. The overhead garage door is configured as a plurality of horizontally oriented, elongated sections hingedly joined along adjacent edges to form the vertical door. The ends of the sections are movably mounted in vertical tracks at each edge of the large opening. The upper ends of the tracks curve interiorly to a horizontal position so that when the overhead garage door is opened, it is raised vertically into an elevated, horizontal position inside the enclosure. In this manner, the overhead garage door is suspended overhead and out of the way when it is open to its fullest extent, thereby leaving a relatively unobstructed entrance to the garage, warehouse, or the like.
From the foregoing, it is clear than an overhead garage door of any significant size will be quite heavy to lift vertically from its closed position to the horizontal, open position. Accordingly, it is customary to mount torsion spring apparatus, electrically operated door openers, and the like, to assist the operator in raising and lowering the overhead garage door between the closed and opened positions.
Due to the length of the sections in the overhead garage door, there is a tendency for the sections to sag downwardly when the overhead garage door is raised to the open or elevated position. Furthermore, wind loading is an important consideration when the overhead garage door is in the closed or vertical position. It is, therefore, customary to mount longitudinal struts on the back side of each overhead garage door section in order to impart the necessary rigidity to the section. The conventional strut is generally fabricated from sheet metal and is formed into a U-shaped configuration in cross section with an integral flange at the end of each arm of the U-shape. The flanges have holes therein to permit the strut to be bolted directly to the back of the section.
However, many factors cause the section of an overhead garage door to be curved out of alignment. For example, overhead garage door sections fabricated from wood will warp from such causes as exposure to moisture, grain direction in the wood, different wood types in the various parts of the section. Additionally, the weight of the section itself and the wind loading to which the total overhead garage door is exposed will cause it to be distorted out of alignment. This distortion can either be concave or convex relative to the exterior or visually exposed portion of the overhead garage door when in the closed position.
Until the advent of the present invention, there has been no satisfactory apparatus or method for compensating for these factors which cause the section to be curved out of alignment. It would, therefore, be an advancement in the art to provide a novel apparatus and method for applying a corrective tensile force to a section of an overhead garage door. Such an apparatus and method is disclosed and claimed herein.